Template css overriding sourcecoast "hover" css for buttons?

It sounds like you're on the right track. It's usually some CSS style that's getting priority. If it was live, I would jump onto the browser developer tools and try to pinpoint which style was the culprit. But from your screenshots, it looks like you're already using the browser dev tools and may be familiar with it already?

I would suggest looking for where the element is getting its margin and padding, maybe also line-height or height. Your browser looks like Firefox. Usually, I use Chrome which allows you to easily turn off a style on an element and see if there's a change. If Firefox has that option as well, go into the padding/margin/line-heights and selectively turn them off one-by-one to see if anything changes.

-Melissa